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Understanding Spinal Disk Problems -- Herniated Disk

Under stress, a disk's inner material may swell, pushing through its tough outer membrane. The entire disk can become distorted or bulge in spots. With an injury, all or part of the core material may protrude through the outer casing at a weak spot, pressing against surrounding nerves. If further activity or injury causes the membrane to rupture or tear, the disk material may further extrude, causing pressure on the spinal cord or the nerves that radiate from it. This may result in extreme pain. In the beginning, there may be spasms in the back or neck which will greatly limit your movement. If nerves are affected, you may develop pain that moves into a leg or an arm.

The vast majority of disk injuries occur in the lumbar region of the lower back. Only 10% of these injuries affect the upper spine. Not all herniated disks press on nerves, however, and it is entirely possible to have deformed disks without any pain or discomfort.

Herniated disks are most common in men and women ages 30 to 50, although they also occur in active children and young adults. Older people, whose disks no longer have fluid cores, are much less likely to encounter the problem. People who do regular, moderate exercise are much less likely to suffer from disk problems than sedentary adults. People who exercise tend to stay flexible considerably longer. Maintaining a normal body weight is also important in preventing back problems.

What Causes a Herniated Disk?

Although a violent injury can damage a disk, problems with disks are often brought on by the normal aging process or by everyday activities, such as lifting heavy objects the wrong way, stretching too hard during a tennis volley, or slipping and falling on an icy sidewalk. Any such event can cause the fibrous outer covering of the disk to break or distort to the point that it presses on a spinal nerve, especially if disk material extrudes. Sometimes, a disk swells, tears, or degenerates without any apparent cause.